The skies over Gaza were quiet for a second day Tuesday in the midst of a 72-hour cease-fire, but Israeli negotiators reported no progress in their talks with the Palestinians on a permanent end to fighting in the coastal enclave.

The negotiators talked for a second day in Cairo, focusing on the Jewish state's blockade of Gaza, where the Hamas militants running the impoverished strip of land along the Mediterranean say they want a seaport opened to promote economic development.

Israel said the issue should only be dealt with as part of longer term peace talks, fearing that ending the blockade now would allow Hamas to restock weaponry from abroad that could be used against Israel if fighting resumes.

An Israeli official said the gaps between the warring sides were big as they sought to end a month of conflict in Gaza that has left more than 2,000 people dead. In daily attacks, Hamas fired thousands of rockets into Israel and Israel bombarded Hamas targets with aerial strikes.

The Organization of Islamic Cooperation condemned Israel for what it called "war crimes" in Gaza. Saudi Foreign Minister Saud al-Faisal said Israel must embrace peace if it hoped to survive as a nation.

"Standing united to back the rights of the Palestinian people will make the world fully aware that Israel cannot continue its aggression against the Palestinians without having to pay the price. Israel should be aware that peace is the only option for survival,'' he said.

Britain said it would suspend 12 licenses to export military items to Israel if the current cease-fire expired and fighting continued.

Hamas is calling for a complete end to an Israeli-Egyptian blockade that has prevented Palestinians from leaving Gaza and made the majority of its residents dependent on humanitarian aid.

Israeli said it would not loosen the restrictions unless it can ensure the demilitarization of Hamas.

Humanitarian groups are warning that the fighting has created a humanitarian catastrophe in Gaza.

The WFP took advantage of the cease-fire that started on Sunday to begin one-time deliveries of rice and wheat flour to 143,000 families. It said that security permitting, the distribution would be complete within two weeks.